Java tutorial
// // Licensed to the Apache Software Foundation (ASF) under one // or more contributor license agreements. See the NOTICE file // distributed with this work for additional information // regarding copyright ownership. The ASF licenses this file // to you under the Apache License, Version 2.0 (the // "License"); you may not use this file except in compliance // with the License. You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, // software distributed under the License is distributed on an // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY // KIND, either express or implied. See the License for the // specific language governing permissions and limitations // under the License. // package com.cloud.agent.direct.download; import com.cloud.utils.exception.CloudRuntimeException; import org.apache.commons.collections.MapUtils; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager; import org.apache.commons.httpclient.HttpStatus; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.io.IOUtils; import org.apache.log4j.Logger; import java.io.File; import java.io.FileOutputStream; import java.io.InputStream; import java.io.OutputStream; import java.io.IOException; import java.util.HashMap; import java.util.Map; public class HttpDirectTemplateDownloader extends DirectTemplateDownloaderImpl { protected HttpClient client; private static final MultiThreadedHttpConnectionManager s_httpClientManager = new MultiThreadedHttpConnectionManager(); public static final Logger s_logger = Logger.getLogger(HttpDirectTemplateDownloader.class.getName()); protected GetMethod request; protected Map<String, String> reqHeaders = new HashMap<>(); public HttpDirectTemplateDownloader(String url, Long templateId, String destPoolPath, String checksum, Map<String, String> headers) { super(url, destPoolPath, templateId, checksum); s_httpClientManager.getParams().setConnectionTimeout(5000); s_httpClientManager.getParams().setSoTimeout(5000); client = new HttpClient(s_httpClientManager); request = createRequest(url, headers); String downloadDir = getDirectDownloadTempPath(templateId); createTemporaryDirectoryAndFile(downloadDir); } protected void createTemporaryDirectoryAndFile(String downloadDir) { createFolder(getDestPoolPath() + File.separator + downloadDir); File f = new File(getDestPoolPath() + File.separator + downloadDir + File.separator + getFileNameFromUrl()); setDownloadedFilePath(f.getAbsolutePath()); } protected GetMethod createRequest(String downloadUrl, Map<String, String> headers) { GetMethod request = new GetMethod(downloadUrl); request.setFollowRedirects(true); if (MapUtils.isNotEmpty(headers)) { for (String key : headers.keySet()) { request.setRequestHeader(key, headers.get(key)); reqHeaders.put(key, headers.get(key)); } } return request; } @Override public boolean downloadTemplate() { try { int status = client.executeMethod(request); if (status != HttpStatus.SC_OK) { s_logger.warn("Not able to download template, status code: " + status); return false; } return performDownload(); } catch (IOException e) { throw new CloudRuntimeException("Error on HTTP request: " + e.getMessage()); } finally { request.releaseConnection(); } } protected boolean performDownload() { s_logger.info("Downloading template " + getTemplateId() + " from " + getUrl() + " to: " + getDownloadedFilePath()); try (InputStream in = request.getResponseBodyAsStream(); OutputStream out = new FileOutputStream(getDownloadedFilePath());) { IOUtils.copy(in, out); } catch (IOException e) { s_logger.error("Error downloading template " + getTemplateId() + " due to: " + e.getMessage()); return false; } return true; } }